Circuit-controlling mechanism.



M. W. DAY.

CIRCUIT eoNTRoLLINe MEGHANISM.

4 APPLIOATION FILED 00T. 17, 1906. 935 ,092 4 Patented Sept. 28, 1909.

l 2 SHEETS-SHEET 1. O @D INVENTDR MAxWE 1 1. DAY.

h Ll

we qq M. W. DAY.

GIRGUIT GONTROLLING MBGHANISM.

APPLICATION FILED 00T. 17, 1906.

Patented Sept. 28, 1909.

2 SHEETS-SHEET 2.

AULA

.INVENTUR HEMI MAxW ELLW. DAY.

Www-:5355

, UNrTED STATES PATENT cierren. y

MAXWELL W. DAY, F SCHENECTADY, NEW YORK, ASSIGNORYTO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

CIRCUIT-CONTROLLING MECHANISM.

Specication of Letters Patent.

Patented Sept. 28, 1909.

Application filed October 17, 1906. Serial No. 339,319.

specification.

rIhis invention relates to circuit-controlling devices which automatically open an electric circuit in case the amount of current flowing therein is abnormal, and more particularly to devices of this class which are arranged to prevent the closing of the circuit when there is an overload upon the circuit.

It has been proposed to connect an automatic circuit-breaker and a switch i'n series, the arrangement being such that the .automatic circuit-breaker is irst closed and then the circuit is closed by means of the switch.

In carrying out my invention two autoy matic circuit-breakers are connected in the circuit to be controlled and are provided with common operating means so that either circuit-breaker may be 4closed and the cir*A cuit may then be completed by closing the other breaker. ln case an overload exists upon the circuit the breaker which was first closed will be automatically tripped and will immediately open the circuit, so that it is impossiblejto keep the circuit closed as long 'as the overload persist-s. If desired, an automatic circuit-breaker may be connectedv in each lead of the circuit to be controlled, so that all leads are protected, a common operating means for the circuit-breakers being provided as above described.

'.Ihe object of the invention is to provide a circuit-controlling device by means of which the closing of the circuit is rendered impossible in case conditions are such that the closing of' the circuit will produce an abnormal flow of current therein; to arrange l a mechanism operated by a rocking handle so that the circuit is closed by two movements of the' handle in different directions, regardless of the direction in which the first movement. is made; to cause the operating vhandle to automatically assume a neutra-l position when released by the operator; and in general to improve the construction of devices of this type as more specifically pointed out in the claims.

The invention will bestv be understood by -the cover removed; and Fig. 7

reference to the accompanying drawings, showing one form in which the invention may be embodied, in which- Figure 1 is a sectional view on the line l, l, of Fig. 2; Fig. 2 is a plan view of thc controlling mechanism with the top of the casing removed to show the arrangement ot the parts; Fig. 3 isa sectional view on the line 3, 3, of Fig. 2; Fig. 4C', a view in perspective of the operating shaft with the movable contacts displaced to show the lost motion connections between the shaft and the contacts; Fig. 5 a sectional view on the line 5, 5, of Fig. 2 showing the tripping mechanism; Fig. 6 .a plan view of the left end of the mechanism shown in Fig. 8, with l a diagram showing the connections between the main circuit an'd the branch circuit. l

,My' invention may be embodied in various forms, but l have shown it applied to two automatic circuit-breakers which are so arranged that theywill automatically open in case an abnormal current is flowing through lthe circuit. These. circuit-breakers are mounted in a casing l carrying posts f2 to which the circuit-breakers are firmly secured by means of bolts or other suitable fastenings. A cover 3 for the casing is provided which inclos'es the circuit-breakers andthe operating mechanism so as to protect the entire device. Leads 4 and 5 of the main circuit pass through the casing and are connected throught-he circuit-breakers with the branch circuit to be controlled.

In the arrangement shown in the drawings, two circuit-breakers of the same con'- struction are used. Each circuit breaker is mounted upon a base G, preferably of insulating material, and bolted to the posts 2. The base carries fixed contacts 7 and S with which a bridging contact 9 cooperates, the bridging contact being carried upon an arm 9, preferably of insulating material, mount' ed upon an operating shaft l0. Arcing tips 1l of copperor other suitable material, are mounted vertically above the fixed contacts 7 and 8 upon the walls 12 of an arc-chute by means of which the arc formed when the circuit is opened is directed away from the operating mechanism of the circuit-breaker. Clips lcarrying the fixed contacts 7, are firmly securedto the base 6 and are in electrical connection by means of connectors 1l with the main leads 4' and 5. Clips 15 carvbridging contact.

rying the fixed contacts 8 are secured to the base and are each connected to one end of the windingsof overload coils 16, the other ends of the windings being connected to terminals 17, to which the leads 18 of the branch circuit are secured. Each overload coil is provided with a pivoted armature 19 which is held in normal position by an adj ustable spring 20. A

As shown in Figs. 5 and 6, each armature is providedwith a lug in which is loosely mounted a screw 21 connected to a pivoted latch 22 carrying a trip-plate 23 which engages the arm 9, and holds the bridging contact 9 in a position to close the circuit. Then the parts are in the position shown in Fig. 5 the arm 9a tends to move toward the screw 21, which tendency is resisted by the trip-plate 23,'which is in engagement with the arm 9a. If the pivoted latch is moved to the left in Fig. 5, the trip-plate moves out of engagement with the arm 9, which is then left free to move toward the screw 21. A spiral spring 24 surrounds the hub to which the arm 9a is secured, one end of the spiral spring engaging a stop 25 carried by the casing, and the other end engaging the arm 9a. The hub to which the arm 9a is secured is provided lwith a heel v26, and the spiral spring 24 tends to throw the heel into engagement with the stop 25 in which position the bridging contact 9 is out of engagement with the fixed contacts 7 and 8 and the circuit is opened. TvVhen the circuit is closed by moving the bridging contact into engagement with the xed contacts, the spiral spring 24 is put under tension and the tripplate 23 engages the arm 9a-and locks the If an overload occurs upon the circuit, the armature 19 is attracted by the overload coil and by means of the screw 21 pulls the latch 22 and trip-plate 23 out of engagement with the arm 9a. this occurs .the spring 24 throws the bridging contact 9 out of engagement with the fixed contacts and the circuit is automatically opened. By placingan automatic circuitl breaker in each lead of the circuit complete protection is assured, since, 1f an abnormal current flows in either lead, the circuit breaker in that lead will open, regardless of the amount of current in the other lead.

vThe shoulder 50 engages the extension 19a of one of the armatures, while the sleeve 31 engages one end of the lever 27, the other end n of which engages the extension on the other When armature. When the trip-rod 2S is moved to the right by means of the knob 29, both armatures are moved toward their respective overload coils and the .circuit breakers are tripped open in the same manner as though the armatures had been attracted by the coils. As a result of this arrangement the circuit may be opened by hand if desired.

A common operating means for the circuit-breakers, consisting of a rod 10 extends through the casino and is suitably journaled therein. The rofl consists of two sections placed end to end, each section carrying a cross-arm 32 rigidly secured thereto, and the cross-arm 32 being bolted to a plate 33 of insulating' material. As a result of this construction, the sections of the operating shaft are rigidly secured together mechanically so as to form a. single shaft, but the sections are insulated from each other electrically. Un one end of the shaft an operating handle 84 is keyed, by means of which the shaft may be rocked for the purpose of operating the circuit-breakers. A hub 35 -is rigidly secured to the shaft near the operating handle, this hub carrying an arm 36 rigidly secured thereto. Apin 37 is mounted in the arm, while a corresponding pin 38 is rigidly carried by the casing. A spiral spring 39 surrounding the hub has its ends extended parallel to each other and passing over both the pins 37 and 3S. As a result of this arrangement the spring tends to bring the pins 37 and 3S into line with each other and if the arm 36 is moved in either direction the spring 89 is put under strain. @perating sleeves 40 and 41 are rigidly secured to the operating shaft so that themovable contacts 9 may be moved to operative position by-means of the shaft. The operatingsleeve 40 is provided with a lug having surfaces 42 and 43, while the operating sleeve 41 is provided with a lug having surfaces 44 and 45. The lug on the operating Sleeve 40 coperates with a shoulder 46 on the hub which carries one of the movable contacts, while the lug on the operating sleeve 41 cooperates with the shoulder 48 on the hub which carries thegother movable contact. This hub also has another shoulder 47, and the other hub hasa corresponding shoulder not shown in`Fig. 4. The width of these lugs is considerably less than the distancebetween the shoulders with .which they cooperate', and the other shoulders on the hubs, so that there is a lost-motion connection betweenthe operating shaft 10 and the hubs which carry the movable contacts of the circuit-breakers.

The operation of the device is as follows: lf it be assumed that the circuit-breakers are open, the movable contacts will be in the position shown in Fig. 4, in which position the heels 26 are in engagement with the stops V25, when the parts of the mechanism are in normal relation. As shown in that figure, the operating handle 34 is held in its normal position by the act-ion of the spiral springs 39 upon the pins 37 and 38. If it be desired to close the circuit, the operating handle 34 may be rotated to the right in the direction of' the arrow c. The result of this movement will be lthe engagement of the surface 42 with the shoulder 46, thereby establishing a rigid connection between the operating shaft 10 and vone of the. movable contacts 9. As the operating handle 34 is moved in the direction of the arrow c, the movable contact 9 is moved in the direction of the arrow a into engagement with the fixed contacts. When the movable contact reaches this position it is locked by means of the latch 22, as hereinbefore explained. The operating handle 34 is now moved in a direction opposite that of the arrow c, leaving the movable contact 9 in a circuit-closing position, and causing the surface 42 to move away from the shoulder 46. When the operating handle reaches its normal position as shown in Fig. 4, the surface 45 comes into engagement with the shoulder 48 and further movement of the operating handle 34 in a direction opposite to that of thearrow c, causes the other movable contact 9 to be moved in the direction of the arrow to circuit-closing position. This movement closes the circuit, and if the conditions are normal, the second movable contact is locked invcircuit-closing position by its latch 22. lvVhen the operating handle 34is released, the spring 39 returns 'it .to normal position, as shown in Fig. 4, and the circuit remains closed, since the movable contacts of both circuit-breakers are in engagement with their-fixed contacts. If an overload should occur upon the circuit, the

armature 19 would be attracted and the circuitbreakers would open the circuit. lf, however, conditions upon the circuit were such that when the circuit is closed an abnormal current flows' therein, the abnormal current would begin to flow as soon as the second movable Contact, which was moved in the direction of the arrow b, engaged its fixed contactswthereby completing the .circuit, and as a result of the abnormal current,

.the overload coil` controlling the first movable contact would be energized,thereby permitting` the spring 24 to move the contact to open the circuit. This movement is possible since at the time the circuit is finally closed by moving the `second contact in the direction of the arrow b, the space between the surface 42-and the shoulder 46 is more than sufficient to permit the first .movable-contact to move in a direction opposite the arrow a and into engagement with its stop 25.

It is evident that it makes no difference Vwhether the operating handle is first moved in the direction of the arrow c or in an opposite direction, since it is immaterial which circuit-breaker is first closed, and therefore, two movements of the operating handle will always close the circuit, so that no delay is occasioned if the operator should first move the operating handle in one direction i'atlier than the other. It. is furthermore apparent that it is impossible for the operator to hold the circuit closed, since after closing one circuit-breaker it is necessary to move the operating shaft entirely out of operative engagement with that circuit-breaker in order to close the other. The opeiating handle is returned to its normal position by means of the spring 39, and hence, when the circuit is to be closed, the operating means is always found in the. same position. It is evident that my invention may be embodied in many other forms than that shown and described, and I therefore, do not wish to be restricted to the particular 'forni herein shown, but intend to cover by the claims all changes and modifications which are lwithin the spirit and scope of my' invention..

What ll claim as new and desire to secure by Letters Patent of the United States, is,-

"1. In a circuit controlling mechanism, the combination. with a plurality of circuit breakers automatically opened by abnormal variationsvof current in the circuit, of a coin mon operatingniember biased to a neutral position in inoperative relation to said circuit breakers and movable at will from said neutral position, and connections between said memberr and said circuit breakers whereby said membei' may be brought into operativel relation to any of said circuit breakers by movement of said member andl thereby any of said circuit breakers may be closed independently of tlie-others.

2. In a circuit controlling'inechanism, the combination with a plurality of circuit breakers automatically opened by abnormal variations of current in the circuit, of a common .operating member biased to a neutral position in inoperative relation to said circuit breakers and movable at will from said neutral position, and a lost motion connectio'n between said member and ea'ch of said circuit breakers, whereby said member may be brougl'it into operative relation to any of said circuit breakers by movement of .said member and thereby any of said circuit breakers may be closed independently of the others and be left free to open when said member is in inoperative relation thereto.

3. InV a circuit controlling mechanism, the combination with a plurality of circuit breakers automatically opened by abnormal variations of. current in the circuit, of acommon operating member biased to a neutral position in--inoperative relation to said'cir-y cuit breakers 'and movable at will from said neutral posi-tion, connections between said member and said circuit breakers whereby said member may be brought, into operative relation to either of said circuit breakers by movement of said member and thereby either of said circuit breakers may be closed independently ofbthe other, and manually operated means for simultaneously tripping both circuit breakers.-

4:. In a circuit controlling mechanism, the combination with two' circuit breakers automatically opened by abnormal variations of current in the circuit, of common operating means normally in neutral position to leave both circuit breakers free to open and movable in either direction from said neutral position to close either circuit breaker independently of the other, and means for automatically returning said operating means t'o neutral position.

5. In a circuit controlling mechanism, the combination .with two circuit breakers, each automatically opened by abnormal current in the circuit, of an operating member movable in different directions, and a lost motion connection between said member and each of said circuit breakers whereby'the movement of said member in one direct-ion closes one circuit breaker independently of the other and movement in the other direction closes the other circuit breaker and leaves the first free to open.

G. Ina circuit controlling mechanism, the

combination with two circuit breakers, each automatically opened by abnormal current in the circuit, of a rockingoperating member for closing either of said circuit breakers and subsequently closing the other circuit breaker.

of engagement with the operating means, of

common operating means normally out of engagement with both circuit breakers and Imovable in either direction into engagement with either circuit breaker, to close it and movable in the other direction out of engagement .with the closed circuit breaker into engagement with the other circuit breaker to close it.

9. In a circuit-controlling mechanism, the combination with a plurality of switches in circuit, movable elements for said switches movable to circuit-closing position, restraining means forholdingsaid elements in switchclosing position, common operating' means for said elements, said operating means engaging the movable element of one of said switches when moved-in one direction and engaging the movable elements of the other switches when moved in another direction, and automatic -means arranged to actuate said restraining means in response to abnormal current and `thereby release said movable elements.

l0. In a circuit-controlling mechanism, the combination with two circuit breakers, each comprising a movable element, a latch for holding saidl element in circuit-closing position, and automatic means for vreleasing said latch upon overload, of a rock shaft movable in opposite directions for moving said elements to a circuit-closing position, and connections between said' rock shaft and said movable elements whereby one element is free from the rock shaft when the other is in engagement therewith.

ll. In a circuit-controlling mechanism, the combination vwith two circuit breakers, each comprising a movable element, a latch for holding said element-in circuit-closing position, and automatic means for releasing said latch upon overload, of a rock-shaft, a projection on said rock-shaft for engaging one element .when said shaft is rocked in one direction, and a projection on said shaft for engaging the other element when the shaft is rocked in the other direction.

In witness whereof, I have hereunto set my hand this 16th day of October, 1906.

. MAXWELL lW. DAY. Witnesses:

BENJAMIN B. HULL,

HELEN ORFORD. i 

